1. Field of the Invention
This invention relates to work producing cycles and, more particularly, to a high efficiency system with a working fluid that uses ambient conditions as a primary heat source and an internal heat exchange mechanism with a turbine and compressor wherein cool turbine exhaust is used to reduce compressor work and turbine exhaust is reheated by compression heat and the compressor and turbine are a unitary structure.
2. Background Art
A conventional system for developing a power cycle typically comprises a boiler, turbine, condenser and pump. Heat is supplied to the boiler by a fossil fuel to convert an operating fluid into a high pressure vapor or gas for use as the working medium. The vapor is expanded in the turbine to produce a work output. In a heat rejection mechanism for the cycle, exhaust vapor from the turbine enters the condenser wherein sufficient heat is removed to condense the vapor. Saturated liquid is delivered to a pump, which raises the pressure to the saturation pressure corresponding to the boiler temperature and thereafter the liquid is delivered to the boiler where the cycle repeats.
Standard systems use a heat source and heat sink to establish a temperature gradient to create heat flow. With a temperature differential created, a working fluid is caused to flow as a result of pressure and/or volumetric differential.
The applicability of any system hinges on the efficiency of the cycle. One apparent flaw in prior art systems is the fact that high work input is a necessary result of creating a differential by developing very high pressures and temperatures through the addition of heat. Generally, in prior art systems, the amount of work required to compress the vapor back to its saturation pressure has been greater than the work extracted from the system through the turbine. The work input that is required to compress the vapor is functionally dependent upon a temperature differential established to generate heat flow in the system. Heretofore, efforts have been made to improve efficiency by utilizing latent or waste heat to reduce heat input.
U.S. Pat. No. 5,107,682 issued Apr. 28, 1992, to applicant, discloses an invention aimed at solving the shortcomings of prior art power cycle systems by using fluid exhaust of the turbine to cool the fluid of the compressor. While this invention yields an extraordinarily high efficiency, non-polluting cycle, further enhancement of heat exchange between the compressor and turbine exhaust and greater structural simplicity was sought.